Impact of keratoprosthesis implantation on retinal and visual pathway function assessed by electrophysiological testing.

PURPOSE: To investigate the impact of Boston Type I Keratoprosthesis (BI-Kpro) implantation on retinal and visual pathway function, respectively, assessed by full-field electroretinography (ERG) and visually evoked potentials (VEPs). METHODS: This is a prospective interventional longitudinal study, and patients with BI-Kpro implantation were assessed preoperatively and at 3 and 12 months after surgery. ERG, flash, and pattern-reversal VEPs (15' and 60' checks) along with visual acuity (VA) were performed. RESULTS: A total of 13 patients (24 to 88 years of age) were included. Mean baseline VA (logMAR) improved from 2.30 to 1.04 at 3 months and to 1.00 at 12 months. Flash VEPs were normal in 6 (46%) patients and in 10 (77%) patients at the 12-month follow-up. PVEP was non-detectable in all patients preoperatively for both check sizes. For 15' check size, 6 (46%) patients showed responses after 3 and 12 months except for 1 patient with normal responses at 12 months with the remaining non-detectable. For 60' checks, 11 (85%) patients had responses 3 months after surgery with only 9 (70%) showing responses at 12 months. Abnormal full-field ERGs were found in all patients preoperatively. Amplitude improvement was found in 10 (77%) patients from baseline to 3 months and in 8 (62%) patients from the 3- to the 12-month follow-up. CONCLUSIONS: In this small cohort of patients with BI-Kpro implantation, a remarkable improvement on visual function quantitatively assessed by electrophysiological testing was found in the majority of cases. Visual electrophysiological testing can contribute to objectively assess functional outcomes in this population.

B-scan ultrasound, visual electrophysiology and perioperative videoendoscopy for predicting functional results in keratoprosthesis candidates.

BACKGROUND/AIMS: We analysed the ability of B-scan ultrasound, ocular electrophysiology testing and videoendoscopic examination for predicting visual prognosis in Boston Type 1 keratoprosthesis (KPro-1) candidates. Indirect anatomical and electrophysiological findings and results from direct endoscopic evaluations were correlated with postoperative functional data. METHODS: In this prospective and interventional study, we included 13 individuals who had previously been indicated for Kpro-1 surgery. All subjects underwent preoperative screening, including ophthalmic evaluation, B-scan ultrasound, electrophysiological testing, and perioperative intraocular videoendoscopic evaluation (VE). B-scan ultrasound, electrophysiological testing, and VE evaluation results were categorised as favourable or unfavourable predictors of postoperative functional results according to predefined criteria. The predictability values of B-scan ultrasound, electrophysiological testing, and VE prognostication were calculated based on the visual acuity level achieved. RESULTS: All surgeries and perioperative VEs were uneventful. Preoperative best-corrected visual acuity (BCVA) ranged from light perception to counting fingers. The 1-year postoperative BCVA was better than 20/200 (satisfactory visual acuity result) in 10 eyes (76.9%) and 20/40 or better in 5 eyes (38.5%). B-scan ultrasound presented a positive predictive value (PPV) of 85.7% for satisfactory postoperative visual acuity, electroretinography showed a PPV of 66.7%, and visual evoked potential presented a PPV of 66.7%. The perioperative VE PPV of a negative finding for satisfactory visual acuity was 100%. CONCLUSIONS: Fundoscopic visualisation by intraocular VE is a minimally invasive procedure that can be used to predict functional outcomes in keratoprosthesis candidates. This technique demonstrated better prognostication in keratoprosthesis candidates than B-scan ultrasound and electrophysiological testing.

Boston Type I Keratoprosthesis: Antibacterial Resistance and Microbiota Evaluation of Soft Contact Lenses.

PURPOSE: To evaluate microbiota colonizing soft contact lenses (CL) in eyes with Boston type I keratoprosthesis (BKPro), and determine the prevalence of resistance to fourth-generation fluoroquinolone (FQ). DESIGN: Prospective, observational study. SUBJECTS: Patients with BKPro using CL as routine who were in postoperative follow-up in the Department of Ophthalmology of the Federal University of Sao Paulo, and volunteered to participate in the study. All patients were under a prophylactic scheme of topical 0.5% moxifloxacin 3 times a day and topical 5% povidone-iodine (PI) at the time of CL exchange. METHODS: Patients on scheduled replacement scheme of CL had their lenses removed and sent for microbiological analysis. Standard culture methods were used for microorganism identification and susceptibility to different antibiotics was tested. Main outcome measure was prevalence of resistance to fourth-generation FQ. RESULTS: Among the 19 eyes, 12 eyes (63%) had at least 1 positive bacterial culture. The most prevalent isolates were Staphylococcus epidermidis and other coagulase-negative staphylococci. Actinomyces viscosus was isolated in 1 CL. Fungal cultures were all negative. Of the 12 eyes with culture bacterial growth, resistance to fourth-generation FQ (0.5% moxifloxacin) was identified in 6 different eyes (50%). None presented infectious complications. CONCLUSIONS: FQ-resistant bacteria were isolated in some patients. Although our prophylactic antibiotic regimen has been efficient in preventing bacterial infection, this analysis demonstrated that prophylaxis with PI and low FQ dose might increase resistance to antibiotics. Investigations in this field may help to outline future changes of prophylactic guidelines and therapeutic strategies.

Anterior segment optical coherence tomography findings in type I Boston keratoprosthesis.

PURPOSE: To report the results of high-resolution anterior segment optical coherence tomography of patients implanted with a type 1 Boston keratoprosthesis (KPro). METHODS: The retrospective study cohort included 11 eyes of 11 patients (average age, 58.4 years; range, 34-83 years). All subjects underwent anterior segment optical coherence tomography at a single posteoperative time point. The main outcome measures were retro-backplate and retro-optic membrane formation, thinning and gap formation of the corneal carrier graft (melting), and degree of angle closure. RESULTS: Preoperative diagnoses included chemical burn (55%), failed corneal transplant (36%), and Stevens-Johnson syndrome (9%). The mean postoperative follow-up duration was 38.5 (range, 12-72) months. The most frequent findings of anterior segment optical coherence tomography were retroprosthetic membrane formation (63%, 7/11), thinning of the corneal carrier graft (melting; 55%, 6/11), and a narrow or closed angle (91%, 10/11). Other less common findings were epithelial growth over the optic surface and periprosthetic cyst formation. Retroprosthetic membrane formation was observed in all patients with melting (6/11). CONCLUSIONS: Detailed postoperative examination and visualization of subtle changes of keratoprosthesis implanted eyes by slit lamp biomicroscopy are often difficult. Anterior segment optical coherence tomography is a useful, noninvasive, and quantitative imaging technique that provides useful information to postoperatively monitor the anatomic stability of an implanted keratoprosthesis.

Anterior segment optical coherence tomography findings in type I Boston keratoprosthesis / Achados de tomografia de coerência óptica do seguimento anterior em ceratoprótese de Boston tipo I

ABSTRACT Purpose: To report the results of high-resolution anterior segment optical coherence tomography of patients implanted with a type 1 Boston keratoprosthesis (KPro). Methods: The retrospective study cohort included 11 eyes of 11 patients (average age, 58.4 years; range, 34-83 years). All subjects underwent anterior segment optical coherence tomography at a single posteoperative time point. The main outcome measures were retro-backplate and retro-optic membrane formation, thinning and gap formation of the corneal carrier graft (melting), and degree of angle closure. Results: Preoperative diagnoses included chemical burn (55%), failed corneal transplant (36%), and Stevens-Johnson syndrome (9%). The mean postoperative follow-up duration was 38.5 (range, 12-72) months. The most frequent findings of anterior segment optical coherence tomography were retroprosthetic membrane formation (63%, 7/11), thinning of the corneal carrier graft (melting; 55%, 6/11), and a narrow or closed angle (91%, 10/11). Other less common findings were epithelial growth over the optic surface and periprosthetic cyst formation. Retroprosthetic membrane formation was observed in all patients with melting (6/11). Conclusions: Detailed postoperative examination and visualization of subtle changes of keratoprosthesis implanted eyes by slit lamp biomicroscopy are often difficult. Anterior segment optical coherence tomography is a useful, noninvasive, and quantitative imaging technique that provides useful information to postoperatively monitor the anatomic stability of an implanted keratoprosthesis.

RESUMO Objetivos: Reportar os resultados das imagens de pacientes com Ceratoprótese de Boston tipo I (KPro) usando tomografia de coerência óptica de alta resolução do seguimento anterior (AS-OCT). Métodos: Nós realizamos um estudo retrospectivo de pacientes submetidos à KPro. Um total de 11 olhos de 11 pacientes foram incluídos. As imagens de AS-OCT foram realizadas em um único tempo de pós-operatório. Os principais resultados incluem formação de membrana retroprostética atrás do prato posterior e atrás do cilindro ótico, afinamento e lacunas na córnea doadora (melt) e graus de ângulo fechado. Resultados: Os diagnósticos pré-operatórios inclui queimadura química (55%), falência pós transplante de córnea (36%) e síndrome de Stevens Johnson (9%). A idade média foi de 58.4 anos (escala, 34-83 anos). A média de tempo de pós-operatório foi de 38.5 meses (escala, 12-72 meses). Os achados mais frequentes de AS-OCT foram: membrana retroprostética, 63% (7/11); afinamento da córnea doadora (melting), 55% (6/11); angulo estreito ou fechado, 91% (10/11). Outros achados menos comuns foram crescimento epitelial sobre a superfície ótica e cistos periprostéticos. Todos os pacientes com melting (6/11) apresentaram membrana retroprostética. Conclusões: O exame pós-operatório e a visualização detalhada das mudanças em olhos com KPro pela lâmpada de fenda pode ser difícil. AS-OCT é uma técnica de imagem útil, não invasiva e quantitativa que permite o monitoramento da estabilidade anatômica no seguimento de KPro implantadas.

A Comparative Study of Full-Thickness Blepharotomy Versus Transconjunctival Eyelid Lengthening in the Correction of Upper Eyelid Retraction in Graves' Orbitopathy.

BACKGROUND: The study was designed to compare the outcome of full-thickness blepharotomy and transconjunctival eyelid lengthening in the correction of upper eyelid retraction (UER) in patients with Graves' orbitopathy (GO). METHODS: This is a prospective randomized interventional study. Following ophthalmic examination, determination of the ocular surface disease index (OSDI) and photography, 27 patients with UER were randomly assigned to either graded full-thickness blepharotomy (G1) or transconjunctival Müller muscle recession and graded disinsertion of the levator palpebrae superioris muscle (G2). Six months later, patients were reevaluated. Digital images were analyzed with the assistance of customized software. A standardized "normal range" of upper eyelid height and contour was calculated based on healthy controls. The outcome of the two groups was compared. RESULTS: Forty-seven eyelids of 27 patients (19 female) with UER were included. Twenty-seven eyelids (15 patients) were allocated to G1 and 20 eyelids (12 patients) to G2. On average, surgery lasted 37.46 ± 5.73 min in G1 and 32.70 ± 8.39 min in G2. Based on the margin reflex distance, 93% of the eyelids in G1 and 85% in G2 were within the normal range after surgery. The corresponding figures for lid contour were 63 and 55%. Both groups displayed significant improvement in OSDI scores. No significant difference was observed in the overall comparison. CONCLUSIONS: The two surgical techniques were equally effective in the treatment of UER from GO. Postoperative contour outcomes were considerably worse in patients with severe UER than in patients with mild or moderate UER, regardless of group. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to Table of Contents or the online Instructions to Authors www.springer.com/00266 . Study registered on ClinicalTrial.gov number: NCT01999790.

Results with the Boston Type I keratoprosthesis after Acanthamoeba keratitis.

PURPOSE: To report the outcomes of implantation of the Boston Type I keratoprosthesis in three patients with Acanthamoeba keratitis (AK), a severe infection that can lead to significant visual loss. OBSERVATIONS: Case series reporting three patients with difficult cases of AK that needed multiple corneal transplantations and glaucoma surgeries. All patients were implanted with the Boston Type I keratoprosthesis device. The main outcomes measure were the visual function and anatomical retention after implantation of the Boston Type I keratoprosthesis. All patients retained the device over the long-term and had good visual function. In one patient a retroprosthetic membrane developed and in another patient an epithelial lip developed over the anterior surface of the keratoprosthesis. The visual acuities range from 20/25 to 20/80 in the implanted eyes. CONCLUSIONS AND IMPORTANCE: The Boston Type I keratoprosthesis resulted in good anatomic and functional results after multiple graft failures after AK.